The invention relates to iodinated fatty acid esters and iodinated fatty acids and derivatives thereof obtained by iodohydrination involving the introduction of alkylsilylated derivatives with alkaline iodides used in the treatment of endemic goitre and pharmaceutical compositions containing them. They can also be used as contrast compounds in radiology and as a vehicle for chemiembolisation.
Endemic goitre is a deficiency disease which constitutes one of the most serious problems of public health confronting the World Health Organisation (WHO). According to official WHO records, a thousand million individuals, that is 20% of the population of the world, is affected by an iodine deficiency, mainly in developing countries (Hetzel B. S., Potter B. J. and Dulberg E. M. The iodine deficiency disorders: nature, pathogenesis and epidemiology. World Rev. Nutr. Diet. 62: 59-119 (1990)). Almost all of these countries are affected with very variable degrees of prevalence. In the most severely affected regions, it is possible to count up to 80% of subjects suffering from thyroid dysfunction: this is manifested by the appearance of unattractive hypertrophy of the glands which can develop into secondary hypothyroidism with neurological problems. Adolescent girls and women of child-bearing age are most widely exposed and can give birth to a high proportion of up to 10% of newborn babies suffering from a particular form of irreversible mental disability known as endemic cretinism and considered as the most threatening medical and social complication.
It is universally accepted that an iodine deficiency in the diet is the primary and predominant cause of this nutritional scourge.
The geological nature and the geographical environment therefore appear to be the main factors determining this situation although certain dietary factors are incriminated as aggravating secondary causes. The appropriate treatment therefore involves supplementing deficient populations with additions of iodine covering physiological requirements.
Theoretically, this objective is easy to achieve. However, experience over recent decades has shown that the traditional vehicles for iodine supplementation (drinking water, table salt, bread -flour) encounter major problems in diffusion associated with the transportation, storage and consumption conditions, in (sub) tropical regions. In fact, iodine is administered in the form of sodium or potassium iodide or iodate liberating halogen in a non-storable form in adipose tissues. It is therefore necessary to take the iodinated vehicle daily for years. The nutritional benefits are irregular and slow to obtain, and this form of supplementation does not allow the urgent problems encountered in regions of high prevalence to be overcome rapidly.
There is also an iodinated oil having long-lasting effect known as Lipiodol.RTM. (Societe Guerbet) which, when administered in a single annual oral or parenteral dose, has demonstrated anti-goitre preventive and therapeutic effects. This iodinated oil, designed as a contrast product in radiology, is produced from rare and relatively expensive poppy-seed oil (Somnifer papaverum). Although the high tolerance and curative properties of Lipiodol.RTM. have been known for a long time, this product has not become established as a tool for massive eradication owing to the relatively high cost with respect to the huge requirements of the Third World.